Inertia demand level evaluation method and system for power system containing wind power

Abstract

The invention discloses a wind power-containing power system inertia demand level evaluation method and system, and the method comprises the steps: obtaining a system inertia demand level evaluation model considering inertia time-space characteristics through considering a system inertia time constant model in which wind power participates in virtual inertia support and primary frequency modulation; according to the system inertia demand level evaluation model considering the inertia space-time characteristics, the system inertia demand levels of different nodes at different times can be quantitatively evaluated, and comprehensive reference is provided for safe and stable operation of the system frequency.

Description

Technical Field

[0001] The present invention belongs to the technical field of power system inertia demand assessment, and in particular relates to a method and system for assessing the inertia demand level of a power system containing wind power. Background Art

[0002] In recent years, the traditional power system dominated by synchronous machines is accelerating its transformation to a new power system dominated by renewable energy. Among them, the dynamic frequency change process and inertia level change of the power system deserve further attention and exploration by researchers.

[0003] With the development and improvement of new energy grid-connected technology, new energy equipment such as wind turbines and energy storage units have replaced conventional thermal power units with frequency regulation capabilities on a large scale. Due to the randomness and intermittency of new energy, the frequency safety and stable operation of new power systems with a high proportion of new energy participation have been severely challenged. Therefore, considering the spatiotemporal characteristics of inertia under the actual system can better meet the characteristics of safe and stable operation of the power system, and the inertia demand assessment of the new power system under the support of the spatiotemporal characteristics of inertia and the virtual inertia of wind power can better guide the frequency safety and stable operation of the power grid.

[0004] In the current related research, the inertia demand level assessment methods for wind power systems that consider the spatiotemporal characteristics of inertia lack the inertia level assessment under the characterization of spatiotemporal distribution characteristics, and cannot accurately assess the inertia demand level of the actual node inertia under disturbance. At the same time, there is a lack of research on the quantitative characterization of the time and space difference distribution of inertia at different nodes, which cannot provide a comprehensive reference for the frequency safety and stable operation of the system. For example, the literature considers the minimum inertia and primary frequency regulation capacity assessment method for new energy high penetration power system with stable frequency [J]. Li Dongdong et al. Power System Protection and Control, 2021, 49(23): 54-61. The modeling using the node model is relatively complex, and the influence of key control parameters of wind power on the system inertia demand is not considered; the literature considers the optimization operation strategy of high proportion of new energy power system based on minimum inertia assessment [J]. Ye Chang et al. Power System Technology, 2023, 47(02): 502-516. The spatiotemporal distribution characteristics of the inertia of the system are not considered. In summary, the current research methods lack a quantitative evaluation method for the system inertia level that simultaneously considers wind power inertia support and frequency regulation and its time-space characteristics of inertia. This patent considers the use of comprehensive inertia control for wind power to participate in inertia support and frequency regulation, and takes into account the support of wind power virtual inertia to effectively solve the problem of insufficient synchronous inertia of the system under a high proportion of new energy. At the same time, considering the time and space variation characteristics of inertia, the simplified simulation model and detailed node model are used to quantitatively analyze and evaluate the inertia level of the system.

[0005] For the new power system that includes large-scale wind power participating in inertia support and frequency regulation, it is necessary to base on the quantitative evaluation and simulation calculation of the inertia demand level under the temporal and spatial distribution characteristics of the system inertia, take into account the temporal and spatial characteristics of the node inertia, and fully consider the time and spatial differences in the inertia demand of different nodes to improve the current inertia evaluation process for the new power system. At the same time, the node inertia demand level under the support of wind power virtual inertia meets the necessity of inertia demand evaluation of the power system under the current high penetration rate of new energy. Therefore, how to consider the inertia demand level evaluation method of wind power system containing wind power with temporal and spatial characteristics of inertia has become an urgent problem to be solved. Summary of the invention

[0006] In order to solve the problems existing in the prior art, the present invention proposes a method and system for evaluating the inertia demand level of a power system containing wind power.

[0007] The technical solution of the present invention is as follows:

[0008] A method for evaluating the inertia demand level of a power system including wind power, comprising:

[0009] Obtain the power-frequency and inertia response process equations of the power system and the system frequency response model taking into account wind power participation in virtual inertia support and primary frequency regulation;

[0010] Based on the power-frequency and inertia response process equations of the power system and the system frequency response model, a system inertia time constant model is constructed;

[0011] Based on the system inertia time constant model, a system inertia requirement level assessment model considering the inertia time-space characteristics is obtained;

[0012] Based on the system inertia requirement level assessment model, the inertia requirement level of the power system is assessed.

[0013] Furthermore, the power-frequency and inertia response process equations of the power system are:

[0014]

[0015] Among them, H i is the inertia constant of node i; Δf i is the frequency change of node i; ΔP m,i is the mechanical power change of node i; ΔP e,i is the change of electromagnetic power at node i; Di is the load frequency adjustment coefficient of node i; t is time.

[0016] Furthermore, the method for obtaining the system frequency response model taking into account wind power participation in virtual inertia support and primary frequency regulation includes:

[0017] Based on the wind power control mode, the inertia response and pitch-variable primary frequency regulation control strategy are adopted to construct the frequency dynamic response transfer function G of the wind power frequency regulation unit using the virtual inertia response control method. w (s):

[0018]

[0019] Among them, G w (s) is the frequency dynamic response transfer function of the wind power frequency regulation unit at the source side; T w k is the inertial support response time constant; d is the inertial response coefficient; ΔP w is the change in inertia control power; Δf is the change in power system frequency;

[0020] The frequency dynamic response transfer function G of the wind power frequency modulation unit using variable pitch primary frequency modulation control is constructed. β (s):

[0021]

[0022] Among them, T β k is the wind turbine pitch response time constant; p is the primary frequency modulation coefficient; ΔP β Provides power variation for pitch control; Δf is the frequency variation of the power system;

[0023] In summary, the system frequency response model G considering wind power participating in virtual inertia support and primary frequency regulation is wind (s) is:

[0024]

[0025] Among them, ΔP wind (s) is the total power change under the comprehensive inertia control mode of wind power; G wind (s) is the system frequency response model considering wind power using comprehensive inertia control mode.

[0026] Furthermore, the specific steps of constructing the system inertia time constant model based on the power-frequency and inertia response process equation of the power system and the system frequency response model include:

[0027] According to the initial value theorem, the initial frequency change rate of the power system considering the disturbance of the power system is calculated:

[0028]

[0029] The system inertia time constant model taking into account wind power participation in virtual inertia support and primary frequency regulation is:

[0030]

[0031] Furthermore, the specific steps of obtaining the system inertia requirement level assessment model considering the inertia time-space characteristics based on the system inertia time constant model include:

[0032] The following system inertia requirement level assessment model considering the spatiotemporal characteristics of inertia is constructed using the time-varying node inertia matrix H:

[0033]

[0034] In the formula, H ii (t) and H ij (t) are the system equivalent inertia time constants of nodes i and j at time t respectively;

[0035] Furthermore, at the time t, the system inertia time constant H of nodes i and j is ii (t) and H ij The expression of (t) is:

[0036]

[0037] In the formula, f i (t) and f j (t) are the frequency values ​​of nodes i and j at time t respectively.

[0038] Furthermore, the and They are the frequency change rate of node i and the frequency change rate of node j respectively, which are obtained by measuring the system frequency characteristic curve.

[0039] A system for evaluating the inertia demand level of a power system including wind power, comprising a model acquisition module, a first model construction module, a second model construction module and an evaluation module;

[0040] The model acquisition module is used to obtain the power-frequency and inertia response process equations of the power system and the system frequency response model considering the wind power adopting the comprehensive inertia control mode;

[0041] The first model building module is used to build a system inertia time constant model taking into account wind power participation in virtual inertia support and primary frequency regulation based on the power-frequency and inertia response process equations of the power system and the system frequency response model;

[0042] The second model building module is used to obtain a system inertia requirement level assessment model considering the inertia time-space characteristics based on the system inertia time constant model;

[0043] The evaluation module is used to evaluate the inertia requirement level of the power system based on a system inertia requirement level evaluation model.

[0044] An electronic device comprises a memory and a processor, wherein the memory stores a computer program, and the processor is used to call and run the computer program stored in the memory to execute any of the methods described above.

[0045] A computer-readable storage medium stores a computer program, wherein the computer program implements the steps of any of the above methods when executed by a processor.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] The present invention proposes a method and system for evaluating the inertia demand level of a power system containing wind power. The method takes into account the system inertia time constant model of wind power participating in virtual inertia support and primary frequency modulation, thereby obtaining a system inertia demand level evaluation model that considers the spatiotemporal characteristics of inertia, thereby accurately evaluating the inertia demand level of the actual node inertia under a disturbed state.

[0048] The system inertia requirement level assessment model considering the spatiotemporal characteristics of inertia in the present invention can quantitatively assess the system inertia requirement levels of different nodes at different times, providing a comprehensive reference for system frequency safety and stable operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 Flow chart of the method for evaluating the inertia requirement level of a power system including wind power in an embodiment

[0050] Figure 2 This is a 10-machine 39-node model diagram including wind power participating in frequency support in the application embodiment;

[0051] Figure 3 This is a wind power frequency regulation diagram considering comprehensive inertia control in the application embodiment:

[0052] Figure 4 is a time-varying graph of frequency deviations of some nodes in the application embodiment;

[0053] Figure 5 It is a spatiotemporal difference diagram of inertia of different nodes in the application embodiment. DETAILED DESCRIPTION

[0054] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent modifications of the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0055] Embodiment 1:

[0056] The present invention provides a method for evaluating the inertia demand level of a power system including wind power, such as Figure 1 Shown include:

[0057] Obtain the power-frequency and inertia response process equations of the power system and the system frequency response model taking into account wind power participation in virtual inertia support and primary frequency regulation;

[0058] Based on the power-frequency and inertia response process equations of the power system and the system frequency response model, a system inertia time constant model is constructed;

[0059] Based on the system inertia time constant model, a system inertia requirement level assessment model considering the inertia time-space characteristics is obtained;

[0060] Based on the system inertia requirement level assessment model, the inertia requirement level of the power system is assessed.

[0061] Embodiment 2:

[0062] This embodiment is further designed on the basis of the first embodiment in that the specific steps of obtaining the power-frequency and inertia response process equation of the power system and the system frequency response model considering the wind power adopting the comprehensive inertia control mode in this embodiment include:

[0063] The large power grid node system model is mainly divided into unit frequency and node frequency. In order to uniformly characterize the overall frequency change characteristics of the power system, the system inertia center frequency is defined, and the regional inertia center frequency is used to represent the overall frequency change trend of the region. Assuming that the power system region includes N units:

[0064] The physical quantity of the center of inertia is characterized as follows:

[0065]

[0066] Among them, H i 、f i are the inertia time constant and frequency of the i-th generator in the power grid, respectively, COI is the center frequency of inertia; H T is the moment of inertia of all generators put into operation and;

[0067] The inertia of the power system refers to the change in the mechanical energy inside the system when the power system is subjected to load changes in a short period of time. In the power system, inertia directly affects the stability and reliability of the power system. Therefore, the inertia time constant H is used to measure the inertia level of the power system, and the swing equation is combined to characterize the power-frequency and inertial response process of the new energy power system.

[0068] The power-frequency and inertia response process equations of the power system are:

[0069]

[0070] Among them, H i is the inertia constant of node i; Δf i is the frequency change of node i; ΔP m,i is the mechanical power change of node i; ΔP e,i is the change of electromagnetic power at node i; Di is the load frequency adjustment coefficient of node i; t is time.

[0071] Embodiment three:

[0072] This embodiment is further designed on the basis of the first embodiment in that the method for obtaining the system frequency response model taking into account the participation of wind power in virtual inertia support and primary frequency regulation in this embodiment includes:

[0073] Based on the source-side wind power control mode, the frequency dynamic response transfer function G of the source-side wind power frequency regulation unit using the virtual inertia response control method is constructed. w (s):

[0074]

[0075] Among them, G w (s) is the frequency dynamic response transfer function of the wind power frequency regulation unit at the source side; T w k is the inertial support response time constant; d is the inertial response coefficient; ΔP w is the change in inertia control power; Δf is the change in power system frequency;

[0076] The frequency dynamic response transfer function G of the wind power frequency modulation unit using variable pitch primary frequency modulation control is constructed. β (s):

[0077]

[0078] Among them, T β k is the wind turbine pitch response time constant; p is the primary frequency modulation coefficient; ΔP β Provides power variation for pitch control; Δf is the frequency variation of the power system;

[0079] In summary, the system frequency response model G considering wind power participating in virtual inertia support and primary frequency regulation is wind (s), that is, the overall dynamic frequency response transfer function of the source-side wind power frequency regulation unit is:

[0080]

[0081] Among them, ΔP wind (s) is the total power change under the comprehensive inertia control mode (i.e., under two control modes) of wind power; G wind (s) is the system frequency response model considering the wind power adopting the comprehensive inertia control mode, that is, the overall dynamic frequency response transfer function of the source-side wind power frequency regulation unit.

[0082] Embodiment 4:

[0083] This embodiment is further designed on the basis of the first embodiment in that, in this embodiment, based on the power-frequency and inertia response process equation of the power system and the system frequency response model, the specific steps of constructing the system inertia time constant model include:

[0084] The total generating capacity of the power system is S sys In the case of , the expression of its equivalent inertia parameter is:

[0085]

[0086] Where H is the system equivalent inertia time constant; H SG The inertia time constant provided for the synchronous motor; S SG is the system capacity of the synchronous motor; E SG is the total kinetic energy of a single synchronous motor; S sys is the total system capacity;

[0087] The above expression of power system inertia is only applicable to simple traditional power systems composed of generators, which ignores other renewable energy power generation units. At this time, the power system inertia only comes from the synchronous grid-connected generator sets. The wind power unit provides virtual inertia support when using comprehensive inertia control. The inertia time constant at this time can be expressed as:

[0088]

[0089] Among them, E V The total kinetic energy of virtual inertia provided to the wind power generation unit;

[0090] The sources of inertia on the generation side of the new energy power system are divided into two types: from synchronously connected traditional generators (synchronous inertia E SG ) and wind power generation unit (virtual inertia E V ), both of which offset the frequency change caused by the imbalance of power generation and consumption in the power system by energy exchange. Therefore, the system equivalent inertia time constant is used to characterize the inertia level of the entire power system. The minimum inertia requirement of the system under different working conditions is also characterized by measuring the system equivalent inertia time constant.

[0091] The frequency dynamic response characteristics of the power system refer to the system's ability to actively support the frequency after being disturbed by a certain amount of active power. The frequency can be maintained or restored in time to a specified safe range without frequency drop or collapse. In the early stage of the disturbance, the frequency support is mainly provided by the system synchronous inertia response, thereby delaying the system's initial frequency change rate (RoCoFmax). When the power system is disturbed, the initial frequency change rate of the power system under the condition of disturbance is calculated according to the initial value theorem:

[0092]

[0093] From the above formula, it can be obtained that the system inertia demand level is related to the disturbance power received by the system and the inertia center frequency of the system. Further, the system inertia time constant model taking into account the participation of wind power in virtual inertia support and primary frequency regulation can be obtained:

[0094]

[0095] It can be seen from the above formula that when the system is under the same disturbance size, the frequency change rate increases, the system frequency stability decreases, and the anti-disturbance ability decreases. Therefore, the system inertia demand based on the inertia center frequency theory is mainly quantified by the initial power-frequency change of the system.

[0096] Embodiment five:

[0097] This embodiment is further designed on the basis of the first embodiment in that, in this embodiment, based on the system inertia time constant model, the specific steps of obtaining the system inertia requirement level assessment model considering the inertia time-space characteristics include:

[0098] The spatial distribution characteristics of the system node frequency after the disturbance are not significant, that is, the frequency difference of each node is not large, so the lumped parameter model can be used to analyze the node model of the system, that is, ignoring the transient process of frequency fluctuation between nodes and assuming that the frequency of each node in the system is the same at any time section, specifically:

[0099]

[0100] Where:

[0101]

[0102] Based on the coupling relationship between active disturbance and system frequency change rate, the spatial distribution characteristics of system inertia are explored. When the frequency spatial distribution of the system after the disturbance is significant, that is, the frequency dynamic process between different nodes is quite different, the system inertia shows different inertia levels at different nodes. When a certain node is disturbed, the node inertia at all nodes can be described by a row vector; when the disturbance traverses all nodes, the spatial distribution characteristics of the system inertia can be fully described by all row vectors. Therefore, the space-variable characteristics of the power system can be standardized by the following system node inertia matrix H:

[0103]

[0104] The i-th row in the matrix corresponds to the system inertia time constant measured from each node after the node i is disturbed, that is, H ii With H ij are the system equivalent inertia time constants of nodes i and j respectively;

[0105] Specifically, the elements in the matrix can be described as:

[0106]

[0107] In the formula, f i With f j are the frequency values ​​of nodes i and j respectively, taking the per-unit values.

[0108] Based on the coupling relationship between active disturbance and system frequency change rate, the time distribution characteristics of system inertia are analyzed. The change rate of the inertia center frequency is relatively stable, while the change rate of each generator node frequency has great differences due to the existence of inter-machine oscillation. The amount of node inertia depends on the amount of unbalanced power caused by the disturbance and the dynamic change of node frequency. Assuming that the disturbance amount remains unchanged, since the node frequency change rate is not uniform along the time axis, this will cause the node inertia to change continuously and not be a constant value.

[0109] The following system inertia requirement level assessment model considering the spatiotemporal characteristics of inertia is constructed using the time-varying node inertia matrix H:

[0110]

[0111] In the formula, H ii (t) and H ij (t) are the system equivalent inertia time constants of nodes i and j at time t respectively; the active disturbance and frequency change rate of the inertia of different nodes are measured by the oscilloscope measurement function of the simulation platform, and the node inertia time constants at different times are analyzed and quantified, so as to equivalently evaluate the system equivalent inertia level under the time-space characteristics.

[0112] Embodiment six:

[0113] This embodiment is further designed on the basis of the fifth embodiment in that the system inertia time constant H of nodes i and j at time t in this embodiment is ii (t) and H ij The expression of (t) is:

[0114] In the formula, f i (t) and f j (t) The frequency values ​​of nodes i and j at time t respectively.

[0115] Embodiment seven:

[0116] This embodiment is further designed on the basis of the sixth embodiment in that in this embodiment, and They are the frequency change rate of node i and the frequency change rate of node j respectively, which are obtained by measuring the system frequency characteristic curve.

[0117] Embodiment eight:

[0118] A wind power-containing power system inertia demand level assessment system of the present invention comprises a model acquisition module, a first model construction module, a second model construction module and an assessment module;

[0119] The model acquisition module is used to obtain the power-frequency and inertia response process equations of the power system and the system frequency response model considering the wind power adopting the comprehensive inertia control mode;

[0120] The first model building module is used to build a system inertia time constant model taking into account wind power participation in virtual inertia support and primary frequency regulation based on the power-frequency and inertia response process equations of the power system and the system frequency response model;

[0121] The second model building module is used to obtain a system inertia requirement level assessment model considering the inertia time-space characteristics based on the system inertia time constant model;

[0122] The evaluation module is used to evaluate the inertia requirement level of the power system based on a system inertia requirement level evaluation model.

[0123] Embodiment nine:

[0124] An electronic device comprises a memory and a processor, wherein the memory stores a computer program, and the processor is used to call and run the computer program stored in the memory to execute any of the methods described above.

[0125] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of any of the above methods are implemented.

[0126] Application examples:

[0127] In this example, the evaluation method of the present invention is simulated and implemented, and the simulation object is the IEEE 10-machine 39-node system, and the transient frequency stability analysis is performed using the Matlab / Simulink simulation platform. Based on the existing standard power flow data, the original synchronous generators at the BUS 32 and BUS 34 nodes are replaced with wind farm groups of 440 and 400 doubly-fed wind generators, respectively, and the frequency regulation function of the doubly-fed wind generators is realized. Among them, the replaced doubly-fed wind turbine generator sets have the same model and parameter settings: the rated capacity of the doubly-fed wind turbine generator is 1.6MVA, the rated power is 1.5MW, and the reference voltage is 0.69kV. The improved IEEE 10-machine 39-node system network topology diagram is shown in the figure Figure 2 shown.

[0128] like Figure 3 As shown, (a) is the active disturbance input; (b) is the trend of the wind turbine pitch angle change; (c) is the trend diagram of the system frequency change rate; (d) is the frequency curve; by adjusting the disturbance input of the mechanical power of wind power, changing the parameter value of the wind turbine pitch angle, and at the same time changing the value of the virtual inertia parameter, the virtual inertia support of the wind turbine module is realized. From (c), it can be seen that the system frequency change rate returns to a stable level due to the support of the virtual inertia after the initial fluctuation, that is, the frequency stability is improved, as shown in (d).

[0129] like Figure 4 As shown in the figure, considering observing the frequency trends of some nodes in a short time interval, it can be seen that different nodes show differences in frequency trends at different times, that is, the node inertia levels under time characteristics are different.

[0130] Figure 5 The inertia time constants of different nodes at a certain time node are displayed. Considering the measurement of active disturbance input and frequency change rate of different nodes, the inertia time constant is quantitatively calculated according to the actual quantitative calculation method and recorded. It can be seen that the spatial differences in the inertia levels of different nodes are significant.

[0131] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention.

Claims

1. A method for evaluating the inertia demand level of a power system including wind power, characterized in that: include: Obtain the power-frequency and inertia response process equations of the power system and the system frequency response model taking into account wind power participation in virtual inertia support and primary frequency regulation; Based on the power-frequency and inertia response process equations of the power system and the system frequency response model, a system inertia time constant model is constructed; Based on the system inertia time constant model, a system inertia requirement level assessment model considering the inertia time-space characteristics is obtained; Based on the system inertia requirement level assessment model, the inertia requirement level of the power system is assessed.

2. The method for evaluating the inertia requirement level of a power system containing wind power according to claim 1, characterized in that: The power-frequency and inertia response process equations of the power system are: Among them, H i is the inertia constant of node i; Δf i is the frequency change of node i; ΔP m,i is the mechanical power change of node i; ΔP e,i is the change of electromagnetic power at node i; Di is the load frequency adjustment coefficient of node i; t is time.

3. The method for evaluating the inertia requirement level of a power system containing wind power according to claim 1, characterized in that: The method for obtaining the system frequency response model taking into account wind power participation in virtual inertia support and primary frequency regulation includes: Based on the wind power control mode, the inertia response and pitch-variable primary frequency regulation control strategy are adopted to construct the frequency dynamic response transfer function G of the wind power frequency regulation unit using the virtual inertia response control method. w (s): Among them, G w (s) is the frequency dynamic response transfer function of the wind power frequency regulation unit at the source side; T w k is the inertial support response time constant; d is the inertial response coefficient; ΔP w is the inertial control power change; Δf is the power system frequency change; The frequency dynamic response transfer function G of the wind power frequency modulation unit using variable pitch primary frequency modulation control is constructed. β (s): Among them, T β k is the wind turbine pitch response time constant; p is the primary frequency modulation coefficient; ΔP β Provides power variation for pitch control; Δf is the frequency variation of the power system; In summary, the system frequency response model G considering wind power participating in virtual inertia support and primary frequency regulation is wind (s) is: Among them, ΔP wind (s) is the total power change under the comprehensive inertia control mode of wind power; G wind (s) is the system frequency response model considering wind power using comprehensive inertia control mode.

4. The method for evaluating the inertia requirement level of a power system containing wind power according to claim 1, characterized in that: The specific steps of constructing the system inertia time constant model based on the power-frequency and inertia response process equation of the power system and the system frequency response model include: According to the initial value theorem, the initial frequency change rate of the power system considering the disturbance of the power system is calculated: The system inertia time constant model taking into account wind power participation in virtual inertia support and primary frequency regulation is:

5. The method for evaluating the inertia requirement level of a power system containing wind power according to claim 1, characterized in that: The specific steps of obtaining the system inertia requirement level assessment model considering the inertia time-space characteristics based on the system inertia time constant model include: The following system inertia requirement level assessment model considering the spatiotemporal characteristics of inertia is constructed using the time-varying node inertia matrix H: In the formula, H ii (t) and H ij (t) are the system equivalent inertia time constants of nodes i and j at time t respectively.

6. The method for evaluating the inertia requirement level of a power system containing wind power according to claim 5, characterized in that: The system inertia time constant H of nodes i and j at time t ii (t) and H ij The expression of (t) is: In the formula, f i (t) and f j (t) are the frequency values ​​of nodes i and j at time t respectively.

7. The method for evaluating the inertia requirement level of a power system containing wind power according to claim 1, characterized in that: Said and They are the frequency change rate of node i and the frequency change rate of node j respectively, which are obtained by measuring the system frequency characteristic curve.

8. A system for assessing the inertia demand level of a power system including wind power, characterized in that: It includes a model acquisition module, a first model construction module, a second model construction module and an evaluation module; The model acquisition module is used to obtain the power-frequency and inertia response process equations of the power system and the system frequency response model considering the wind power adopting the comprehensive inertia control mode; The first model building module is used to build a system inertia time constant model taking into account wind power participation in virtual inertia support and primary frequency regulation based on the power-frequency and inertia response process equations of the power system and the system frequency response model; The second model building module is used to obtain a system inertia requirement level assessment model considering the inertia time-space characteristics based on the system inertia time constant model; The evaluation module is used to evaluate the inertia requirement level of the power system based on a system inertia requirement level evaluation model.

9. An electronic device, characterized in that: The electronic device comprises a memory and a processor, wherein the memory stores a computer program, and the processor is configured to call and run the computer program stored in the memory to execute the method according to any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method as claimed in any one of claims 1 to 7 are implemented.

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